Commit Graph

9 Commits

Author SHA1 Message Date
bmeurer
c7d7ca361d [turbofan] Collect invocation counts and compute relative call frequencies.
Add a notion of "invocation count" to the baseline compilers, which
increment a special slot in the TypeFeedbackVector for each invocation
of a given function (the optimized code doesn't currently collect this
information).

Use this invocation count to relativize the call counts on the call
sites within the function, so that the inlining heuristic has a view
of relative importance of a call site rather than some absolute numbers
with unclear meaning for the current function. Also apply the call site
frequency as a factor to all frequencies in the inlinee by passing this
to the graph builders so that the importance of a call site in an
inlinee is relative to the topmost optimized function.

Note that all functions that neither have literals nor need type
feedback slots will share a single invocation count cell in the
canonical empty type feedback vector, so their invocation count is
meaningless, but that doesn't matter since we only use the invocation
count to relativize call counts within the function, which we only have
if we have at least one type feedback vector (the CallIC slot).

See the design document for additional details on this change:
https://docs.google.com/document/d/1VoYBhpDhJC4VlqMXCKvae-8IGuheBGxy32EOgC2LnT8

BUG=v8:5267,v8:5372
R=mvstanton@chromium.org,rmcilroy@chromium.org,mstarzinger@chromium.org

Review-Url: https://codereview.chromium.org/2337123003
Cr-Commit-Position: refs/heads/master@{#39410}
2016-09-14 10:20:48 +00:00
leszeks
1c0c5fda26 [Interpreter] Move context chain search loop to handler
Moves the context chain search loop out of generated bytecode, and into
the (Lda|Ldr|Sda)ContextSlot handler, by passing the context depth in as
an additional operand. This should decrease the bytecode size and
increase performance for deep context chain searches, at the cost of
slightly increasing bytecode size for shallow context access.

Review-Url: https://codereview.chromium.org/2336643002
Cr-Commit-Position: refs/heads/master@{#39378}
2016-09-13 11:09:33 +00:00
leszeks
b28b7e1328 [Interpreter] Remove constant pool type in tests
For historical reasons, the interpreter's bytecode expectations tests
required a type for the constant pool. This had two disadvantages:

 1. Strings and numbers were not visible in mixed pools, and
 2. Mismatches of pool types (e.g. when rebaselining) would cause parser
    errors

This removes the pool types, making everything 'mixed', but appending
the values to string and number valued constants. Specifying a pool type
in the *.golden header now prints a warning (for backwards compatibility).

BUG=v8:5350

Review-Url: https://codereview.chromium.org/2310103002
Cr-Commit-Position: refs/heads/master@{#39216}
2016-09-06 16:11:23 +00:00
mythria
9e3e2ee2dd [Interpreter] Assign feedback slots for binary operations and use them in ignition.
Assign feedback slots in the type feedback vector for binary operations.
Update bytecode-generator to use these slots and add them as an operand
to binary operations.

BUG=v8:4280
LOG=N

Review-Url: https://codereview.chromium.org/2209633002
Cr-Commit-Position: refs/heads/master@{#38408}
2016-08-08 01:16:40 +00:00
oth
769d332619 [interpreter] Filter expression positions at source.
With this change the bytecode array builder only emits expression
positions for bytecodes that can throw. This allows more peephole
optimization opportunities and results in smaller code.

BUG=v8:4280,chromium:615979
LOG=N

Review-Url: https://codereview.chromium.org/2038323002
Cr-Commit-Position: refs/heads/master@{#36863}
2016-06-09 13:33:29 +00:00
oth
5e8f8d4e8c [interpreter] Bytecode register optimizer.
Online optimization stage for reducing redundant transfers between registers.

BUG=V8:4280
LOG=N

Review-Url: https://codereview.chromium.org/1997653002
Cr-Commit-Position: refs/heads/master@{#36551}
2016-05-27 15:59:16 +00:00
oth
25b3fe7961 [interpreter] Introduce fused bytecodes for common sequences.
This change introduces five fused bytecodes for common bytecode
sequences on popular websites. These are LdrNamedProperty,
LdrKeyedProperty, LdrGlobal, LdrContextSlot, and LdrUndefined. These
load values into a destination register operand instead of the
accumulator. They are emitted by the peephole optimizer.

BUG=v8:4280
LOG=N

Review-Url: https://codereview.chromium.org/1985753002
Cr-Commit-Position: refs/heads/master@{#36507}
2016-05-25 09:56:49 +00:00
oth
52600c6b1c [interpreter] Add checks for source position to test-bytecode-generator.
Prints source position information alongside bytecode.

BUG=v8:4280
LOG=N

Review-Url: https://codereview.chromium.org/1963663002
Cr-Commit-Position: refs/heads/master@{#36171}
2016-05-11 12:22:17 +00:00
ssanfilippo
6ae030590d [Interpreter] Refactor bytecode generator test suite.
Bytecode expectations have been moved to external (.golden) files,
one per test. Each test in the suite builds a representation of the
the compiled bytecode using BytecodeExpectationsPrinter. The output is
then compared to the golden file. If the comparision fails, a textual
diff can be used to identify the discrepancies.

Only the test snippets are left in the cc file, which also allows to
make it more compact and meaningful. Leaving the snippets in the cc
file was a deliberate choice to allow keeping the "truth" about the
tests in the cc file, which will rarely change, as opposed to golden
files.

Golden files can be generated and kept up to date using
generate-bytecode-expectations, which also means that the test suite
can be batch updated whenever the bytecode or golden format changes.

The golden format has been slightly amended (no more comments about
`void*`, add size of the bytecode array) following the consideration
made while converting the tests.

There is also a fix: BytecodeExpectationsPrinter::top_level_ was left
uninitialized, leading to undefined behaviour.

BUG=v8:4280
LOG=N

Review URL: https://codereview.chromium.org/1717293002

Cr-Commit-Position: refs/heads/master@{#34285}
2016-02-25 12:07:19 +00:00